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981.
Jie Zhang Tatsunori Sasaki Wei Li Kazuya Nagata Koji Higai Feng Feng Jian Wang Maosheng Cheng Kazuo Koike 《Bioorganic & medicinal chemistry letters》2018,28(7):1194-1197
Considerable attention has been paid to protein tyrosine phosphatase 1B (PTP1B) inhibitors as a potential therapy for diabetes, obesity, and cancer. Ten caffeoylquinic acid derivatives (1–10) from leaves of Artemisia princeps Pamp. (Asteraceae) were identified as natural PTP1B inhibitors. Among them, chlorogenic acid (3) showed the most potent inhibitory activity (IC50 11.1?μM). Compound 3 was demonstrated to be a noncompetitive inhibitor by a kinetic analysis. Molecular docking simulation suggested that compound 3 bound to the allosteric site of PTP1B. Furthermore, compound 3 showed remarkable selectivity against four homologous PTPs. According to these findings, compound 3 might be potentially valuable for further drug development. 相似文献
982.
983.
通过脂质组学分析方法从细胞膜磷脂分布方面探究适应进化酿酒酵母酚酸耐受性机制。主要利用高效液相色谱-质谱(LC-MS)对酚酸胁迫下适应进化菌株和原始菌株脂质成分检测并进行统计学比较分析。检测出565种脂质代谢物,包含细胞膜磷脂185种。相比初始菌株,适应进化菌株细胞膜中磷脂酰胆碱(PC)、磷脂酰乙醇胺(PE)和磷脂酰肌醇(PI)类磷脂分子相对含量增加,含有长链(C32-C36)和双不饱和脂酰链的磷脂分子含量增加。统计学分析表明显著性差异磷脂分子主要为含有长链不饱和脂酰链的PC和PE类磷脂分子。推测适应进化菌株通过膜磷脂重塑提高细胞膜完整性,对酚类抑制物起到选择性屏障作用,从而保持细胞活性。 相似文献
984.
【背景】开发噬菌体产品是一种防控空肠弯曲菌有潜力的策略,但是面临噬菌体分离的挑战。【目的】运用响应面法对宿主菌富集空肠弯曲菌噬菌体的培养条件进行优化。【方法】通过单因素试验分析培养基、培养温度、培养转速、离子添加剂对噬菌体富集效果的影响,以噬菌体回收率为评价指标,采用响应面法优化了空肠弯曲菌噬菌体的富集培养条件。【结果】在37℃条件下进行静置培养时,噬菌体富集培养效果最佳,回收率为354.12%。分离噬菌体的过程包括采样并制备滤液、宿主菌与样品滤液共培养及噬菌体分离与鉴定等环节。应用此方法从鸡粪便中分离空肠弯曲菌噬菌体,与传统的单斑法相比,噬菌体分离率提高了269.23%。【结论】研究优化的宿主菌富集噬菌体培养方法可提高空肠弯曲菌噬菌体的分离效率,为噬菌体的研究提供思路。 相似文献
985.
Heat stress is one of a wide variety of factors causing liver injury, a small heat shock protein (HSP), HSP32, is induced by heat stress in the liver. But the biological function of HSP32 in this injury is unclear. To investigate the underlying role of HSP32, RT-PCR, immunocytochemical staining and ELISA were applied to confirm the expression of HSP32. And the underlying mechanism in the pathogenesis of hepatic dysfunction following hyperthermic challenge and the possible involvement of oxidative stress to induce oxidative deterioration of liver functions in developing mice were investigated in this study. Caspase-3mRNA expression and caspase-3 activity of heated liver were also analysed. The results showed that liver injury caused by chronic heat stress(39 °C, 1.5 h/day for 6 weeks) was reversible, caspase-3mRNA expression and caspase-3 activity of heat treated mice were increased after the first three weeks of heat exposure (P<0.05) and high expression levels of HSP32 were observed throughout the duration of experiment (P<0.01). A strong correlation exists between heat-induced liver injury and the induction of HSP32, which suggested that the reversibility of liver injury is involved in the induction of HSP32 in the hepatic cells under continuing heat stress. 相似文献
986.
酚氧化酶是黑色素合成和昆虫免疫的关键酶, 通常以无活性的酚氧化酶原形式存在。为给黄粉虫Tenebrio molitor遗传分化和免疫防御研究提供参考, 本研究采用PCR和RACE技术克隆了黄、 黑两种色型黄粉虫幼虫的酚氧化酶原基因Tm-ppo, 对其cDNA序列及其推导的氨基酸序列进行生物信息学分析, 采用实时荧光定量PCR检测其在两种色型黄粉虫不同发育阶段mRNA表达水平上的动态变化。结果表明: 从黄、 黑两种色型黄粉虫幼虫中克隆出的两个Tm-ppo cDNA序列全长均为2 199 bp, 碱基序列一致性为99%, 包含一个2 055 bp的开放阅读框, 编码684个氨基酸, 它们的编码蛋白有3个氨基酸差异: 第176位(P→A)、 256位(V→A)和648位(I→M)。这两个基因分别被命名为Tm-ppo-1和Tm-ppo-2 (GenBank登录号分别为JX987235和JX987234)。 Tm-ppo-1和Tm-ppo-2编码的酚氧化酶原异构体蛋白(分别为Tm-PPO-1和Tm-PPO-2)存在一个可能的酚氧化酶原水解活化位点(R50~F51残基之间)和一个双铜结合中心(第196~239位残基和第344~411位残基); 同时含有一个类似巯基酯区域的序列(第579~588位残基)及一个C 末端保守基序(第634~645位残基); 但它们无氨基端疏水信号肽序列, 也不存在跨膜区域。Tm-PPO-1和Tm-PPO-2的二级结构由大量的α 螺旋、 β-折叠和无规则卷曲组成; 三级结构分为前导域(第16~66位残基)、 不相邻的功能域Ⅰ(第3~15位残基和第67~181位残基)、 功能域Ⅱ(第182~419位残基)和功能域Ⅲ(第420~679位残基)4部分。此外, Tm-ppo-1和Tm-ppo-2在黄、 黑两种色型黄粉虫的各发育期均有表达, 并且不同发育阶段的mRNA表达水平呈现明显的变化规律: 幼虫期﹥成虫期﹥蛹期。同时, 环境温度对Tm-ppo-1和Tm-ppo-2的mRNA表达具有显著影响: 与常温对照组(25~30℃)相比, 42℃暴露24 h和48 h的两种色型黄粉虫幼虫、 蛹和成虫的mRNA表达量明显下调。相同试验条件下, 黑色型黄粉虫幼虫和成虫的Tm-ppo-2 mRNA表达量明显高于黄色型幼虫和成虫的Tm-ppo-1 mRNA表达量, 但两种色型黄粉虫蛹的Tm-ppo异构体表达量无显著差异。本研究为进一步探讨黄粉虫的遗传分化和免疫防御提供了有益参考。 相似文献
987.
释放肿腿蜂是控制天牛的环境友好型生物防治方法之一。为评价松褐天牛肿腿蜂Sclerodermus sp.对悬铃木上天牛的防治效果,首先调查明确了荆州城区危害悬铃木的天牛种类主要为光肩星天牛,其幼虫和成虫数量分别占天牛总数量93.78%和95.45%;室内测定结果显示蜂虫比2∶1、1∶1、1∶2时光肩星天牛3个龄期幼虫寄生死亡率分别为86.67%、76.30%、33.34%;野外释放寄生蜂60 d后释放点天牛虫口减退率为52.79%-81.85%。研究结果表明,人工释放松褐天牛肿腿蜂能够有效控制悬铃木上天牛种群。 相似文献
988.
杭州西湖水域可培养异细菌的群落多样性 总被引:9,自引:0,他引:9
自2001年10月~2002年10月对杭州西湖水域可培养异养细菌的群落结构和多样性进行了为期1年的调查。水体中可培养异养细菌的年平均值只有510 CFU/mL。从季节变化来看,温度较低的12月和3月其数量相对较多,分别为809和757 CFU/mL,而温度较高的5月和10月只有327和330 CFU/mL。表层底泥中可培养异养细菌的数量平均为2.27×105 CFU /g (以干泥计),其中长桥湾相对较多,为3.06×105 CFU /g,而湖心泥中只有1.70×105 CFU /g。从季节的变化看,也是冬季的数量比夏季高。调查还发现西湖水域优势菌的优势度高,多样性指数低。在三个湖区连续1年的测定中总共只出现14种类型的菌落,优势菌为假单胞菌属、肠杆菌科和气单胞菌属。水体中优势菌的优势度为36.8%~80.4% ,平均54.5%;多样性指数H介于0.682~1.787之间,平均1.160。底泥中优势菌的优势度为27.7%~72.7% ,平均51.7%;多样性指数H介于0.809~1.774之间,平均1.309。水体中的细菌有95%为革兰氏阴性杆菌,革兰氏阳性菌很少;产色素菌的比例相对较高,其中以产黄色素菌落为主,平均达20.1%;芽孢杆菌所占的比例较低,只有4.24%。而表层沉积物中产黄色素的菌落较少,只有2.07%;芽孢杆菌的比例则相对较高,为14.1%。 相似文献
989.
Guangming Yan Jie Chen Guiying Yang Guangyou Duan Zhiyong Du Zubin Yu Jing Peng Wei Liao Hong Li 《BMC anesthesiology》2018,18(1):192
Objective
To compare the analgesic effects of patient-controlled intravenous analgesia (PCA) with hydromorphone and sufentanil after thoracic surgery on postoperative pulmonary complications (PPCs).Methods
A total of 142 patients who were scheduled for thoracic surgery were randomly allocated to receive PCA with hydromorphone (group A: experimental group): hydromorphone 0.2?mg/kg?+?dezocine 0.5?mg/kg?+?ramosetron 0.6?mg diluted with normal saline to 200?mL; or with sufentanil (group B: control group): sufentanil 3.0μg/kg?+?dezocine 0.5?mg/kg?+?ramosetron 0.6?mg diluted with normal saline to 200?mL. The parameters of intravenous analgesia pump were set as background dose 4?ml/h, PCA dose 1?mL, locking time 15?min. Pain NRS (numerical rating scale), Ramsay sedation score, nausea or vomiting score were evaluated at 0?h, 6?h, 12?h, 24?h, 48?h after operation. The cases of PPCs (atelectasis, pulmonary infection, respiratory failure), CRP (C-reaction protein) and inflammatory cells (white cell count and percentage of neutrophils) and blood gas analysis at 12?h after operation, length of ICU and postoperative stay were recorded for each patient.Results
Data of 136 patients were analyzed. Compared with group B (4[IQR:2,2]), the pain NRS in group A (2[IQR:4,4]) was significantly lower at 6?h after operation (P?=?0.000). The CRP in group A (69.79?±?32.13?mg/L) were lower than group B (76.76?±?43.42?mg/L) after operation, but the difference was not significant (P?=?0.427). No difference of nausea or vomiting was found between group A (7.3%) and group B (5.8%) postoperatively (P?=?0.999). The PPCs were happened in 11 patients in group A (16.2%) and 22 patients in group B (32.4%) and the difference between two groups was significant (P?=?0.027). Seven patients in group A (10.3%) and eighteen patients in group B (26.5%) had clinical evidence of pneumonia and the difference between two groups was significant (P?=?0.014). The length of ICU and postoperative stay in group A were 2.73?h and 1.82?days less than group B respectively but the differences were not significant (P?=?0.234, P?=?0.186 respectively).Conclusion
Compared with sufentanil, hydromorphone may provide better postoperative analgesic effect with less pulmonary complications for patients undergoing thoracic surgery, and it may accelerate patients’ rehabilitation.Trial registration
Randomized Controlled Trials ChiCTR1800014282c. Registered 3 January 2018.990.
Shixiong?YangEmail author Zhuo?Zheng Limi?Mao Jie?Li Bishan?Chen 《Vegetation History and Archaeobotany》2018,27(6):781-799
Identification of pollen grains of cultivated plants is essential in archaeobotanical studies. In this study, we investigated the pollen morphology of 30 species which are representatives of most of the crop plants in southern China, using a light microscope. Our results show that the pollen grains of these species or genera can generally be identified by their size, aperture(s) and exine sculpture. We found that: (1) some cultivated cereals can be distinguished from wild species of Poaceae according to their size frequency combined with their morphological features; (2) the lengths of the equatorial diameter (E), polar axis (P) and the greatest dimension of the lumina (the size of the network sculpturing) of the exine reticulum may be diagnostic features to distinguish some brassicaceous vegetables. There are significant differences between the E and P values among Brassica campestris (B. rapa, oilseed rape, Chinese cabbage), B. alboglabra (B. oleracea var. alboglabra, gai lan, Chinese kale), B. parachinensis (B. rapa var. parachinensis, choy sum, Chinese flowering cabbage) and B. chinensis (B. rapa ssp. chinensis, pak choi), but moderate differences in the longer axis length of the reticulum lumina, which provide potential for identifying species on the basis of pollen grains. We compared the P values and the longer axis length of the lumina of modern specimens of Brassicaceae pollen grains with those of fossil pollen extracted from the Ming-Qing cultural layer in the Fuqikou site at Chongqing, China, and found that the fossil pollen grains of Brassicaceae probably represent vegetable plants related to B. parachinensis. Moreover, we measured the diameters of rice pollen grains from modern paddy fields to assess the pollen size frequency and found that the size range from ~?34 to 38 µm is closely associated with rice pollen in southern China, which can be used to detect pollen signals of human activities in archaeobotanical investigations. 相似文献